2D Texture differences

The most commonly used textures are 2-dimensional. There exist 3 kinds of 2D textures:

1. Texture2D
   Power of two sized (POTS) E.g: 1024²
   These are supported on all OpenGL 1.2 drivers.
   • MipMaps are allowed.
   • All filter modes are allowed.
   • Texture Coordinates are addressed parametrically: [0.0f ... 1.0f]x[0.0f ... 1.0f]
   • All wrap modes are allowed.
   • Borders are supported. (Exception: S3TC Texture Compression does not allow borders)
2. Texture2D
   Non power of two sized (NPOTS) E.g: 640*480.
   GL.SupportsExtension( "ARB_texture_non_power_of_two" ) must evaluate to true.
   • MipMaps are allowed.
   • All filter modes are allowed.
   • Texture Coordinates are addressed parametrically: [0.0f ... 1.0f]x[0.0f ... 1.0f]
   • All wrap modes are allowed.
   • Borders are supported. (Exception: S3TC Texture Compression does not allow borders)
3. TextureRectangle
   Arbitrary size. E.g: 640*480.
   GL.SupportsExtension( "ARB_texture_rectangle" ) must evaluate to true.
   • MipMaps are not allowed.
   • Only Nearest and Linear filter modes are allowed. (default is Linear)
   • Texture Coordinates are addressed non-parametrically: [0..width]x[0..height]
   • Only Clamp and ClampToEdge wrap modes are allowed. (default is ClampToEdge)
   • Borders are not supported.

Note that 1 and 2 both use the same tokens. The only difference between them is the size.